Electric condenser and process of manufacture



Aug. 28, 1928.

' 1,682,031 G. E. BLIZIQTIS ELECTRIC CCNDENSER AND PROCESS oF MANUFACTURE Filed March 21, 1927 2 Sheets-Sheet- 1 N Q N l I l 36 25 o N N INVENTOR.

ATTORNEY Aug. 28, 1928. 1,682,031 v l G. E. BLlzlo'rls u ELECTRIC CONDENSER'AND PROCESS OF, MANUFAGTURE File'dMarcn 2 1. 1927 2 sheets-sheet 2 A TTORNEY INVENToR.

Patented Aug.` 28, 19.28'.

UNITED STATES GEORGE-EPAM BLIZIOTIS, OF NEWARK, NEW JERSEY, ABSIGNOR T CONSOLIDATED RESEARCH LABORATORIES, INC., 0F NEWARK, vNEW NEW JERSEY.

JERSEY, A CORPORATION OF ELECTRIC CONDENSER AND PROCESS OF MANUFACTURE.

Application led March 21. 1927. Serial No. 176,896. y

This invention relates to electric condensers of the type used in connection with radio and' like apparatus for well known purposes.

Such condensers ordinarily consist of flattened coils produced by winding two strips of thin sheet metal foil in layered relation and having interposed between the layers some form of insulation, as by covering each strip with a coating of lacquer or like enamel var- Dish, by an intervening strip of waxed paper,

or other non-conducting material between the layers. l

Commonly, the layers' are arranged one directly over the other, with their edges in register, and if the edges are not amply insulated leakage of current occurs rendering the condenser quite useless.

If the insulation used is of a liquid nature,

as a varnish, and the thin metal strips have o square-edges, which they invariably do, the

jects of the present invention to provide a condenser that is essentially leak-proof, by freason of arranging metal strips of uniform thickness and width in odset or staggered relation in each layer, each strip being individually insulated in addition to a coating deposited on the combined strips comprising the layer prior to its being coiled.

A further feature of importance is to avoid all sharp corners on the inner edge of each strip by shaping the same in a manner to receive and retain a uniform thickness of the enamel as applied to the strips before coalescing, these inner edges at the junction of adjacent flat surfaces, eventually receiving a iillet of the insulating material prior of winding, thus avoiding all possibility of leakage.

Another object is to arrange the ends of the coalesced strips in a manner to prevent leaking thereat. l

Other objects are, to compress the condenser layers by pressure applied on their sides after winding, the extreme ends receiving less pressure thanr the main central portion; to permanently connect the opposite, single strip elements by terminals for the attachment of conductors, and finally, in the provision of a compact, eliicient and inexpensive condenser, together with theA process of its manufacture.

These aims are accomplished by the novel constructlon and combination of parts and defmlteprocesses as hereinafter described and shown 1n the annexed drawings, forming an essentlal part of this disclosure, and in which Figure l is a plan view of an approved form of the apparatus used in the construct1on of the condenser plates.

l Flgure 2 is a side elevational view of the same, partially in section and largely diagrammatical.

' Figure 3 is a plan View of a fragment of the strlp from which the condenser is formed.

Figure 4 is a greatly enlarged transverse section of a portion of the coalesced strip taken on line fl-AL of Figure 3.

Figure 5 is a similar sectional view of a single strip of the film, showing the manner 1n which the inner edge is prepared.

Figure 6 is a fragmentary perspective view of the end of the doubled strip prior to coilmg.

Figure 7 is an end view of the condenser in the form of a cylindrical coil.

Figure 8 is asimilar view showing the coil as flattened.

Figure 9 is a perspective view of a completed condenser as ready for use.

Figure 10 is an enlarged fragmentary transverse section, taken on line 10--10 of Figure 9.

In the drawing, Vthe numerals 15-15 designate rollers carrying coils 16-16 of `metallic foil, as aluminum, tin, etc., and in order to prevent too rapid unrolling of the coiled foil, there is provided idlers 17-17 journalled in supporting levers 18--18 pivoted at 19--19I the outer ends of the levers being furnished with adjustable weights 20-20.

From the rollers 15--15, the foil strips 16-16 pass between rolls 21-21 having oppositely disposed enlarged ends 22-22 to pinch the strips, presenting one of their longitudinal edges 16a and 16" rounded, as seen in Figures 4 and 5, such convex shape readily retaining a coating, the opposite edges 16b and 16h being left untreated.

The strips then enter tanks 247-24 con taining any preferred solvent 25 such as alcohol, benzene, etc. to remove any dirt, grease enamel 38 of a diderent density and and the like therefrom passing around rolls 26-26, to cause complete submergence, and u lthrough openings 27 in the bottom and top ci) a drying oven 28 provided with any preferred heating means, as high resistance coils.

29, steam pipes or hot'air, by which the strips Aare dried, thence over rolls 30-30 and back over rolls 36--36, back through the oven again, entering tanks 37-37- containing around submerging rolls 39-39.

From the lastnamed tanks, the strips again pass through the oven and over rolls 40-40, the strip 16 passing over an additional roll 41 to meet the strip 16 and, because of the still tacky surface, adhere thereto.

The rolls 30, 36, 40 and 41 are offset, from therolls 30', 36 and 40', as shown in'Figure 1, so that, when the strips 16-16 meet, they are in staggered relation, presenting single thicknesses at their outer edges as seen in Figure 3.

From the rolls 40-41 the strips ,pass through the oven l28 and between a pair of squeezing rolls 43, causing the strips to coalesce, thence into a tank 44 and around a submerging roll 45,v the tank 44 containing enamel 46 of still different density, this coating forming a fillet between the rounded edges 16a-46"" and the adjacent side surfaces of the strips as seen in Figure 4, the strips then passing through the oven for a final drying and onto a roll 48.

Disposed above the roll 48 is another roll 49 carrying paper 50 oiled, waxed or otherwise treated to prevent adhesion, and coiled over the strip 16-16 to enterbetween each layer, so that the surfaces will not adhere to each other, the same being held in an even position by spring actuated guide rollers 51;

Aso-

strips will obviously be approximately twice as .thick as the single edge portions, after which the central portion is further .compressed, presentmg miniature bands 53 adjacent the protruding, single thicknesses of the foil edges 16h and 16", these bands terminatin at the rounded edges 16"L and 16a.

hese extending end portions havepassing through them, in electrical engagement, electrical terminals 54--54 to whichl conductors' the insulation of which is evenly distributed and which is compact, eliicient and inexpensive to manufacture.

As changes of construction could be made within the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, 'is

1. An electric condenser comprising a pair of insulated foil strips of equal width, said strips being disposed in staggered relation to each other and formed into a flattened coil having its central portion compressed to form bands near the ends of the coil.

2. An electric condenser comprising a pair of foil strips of uniform width arranged in staggered lateral relation, said strips having their inner edges shaped to present a rounded surface, and an adherent insulation completely covering said strips.

3. An electric condenser comprising a lay- I ered coil composed of a strip formed from two plies of metallic foil uniform in width and arranged in staggered relation, an insulative coating on each ply and over the coalesced strip, the inner longitudinal edges of'each ply being shaped to retain insulation, and metallic terminals fixed in the extendin single ply ends of the condenser.

4. An electric condenser comprising a layered coil composed of a strip formed from two plies of metallic foil uniform in width and arranged in staggered relation, an insula-tive coating on each ply and over the coalesced strip, both ends of said strip having its plies separated and folded back upon themselves to prevent current leakage.

5. An electric condenser comprising a layered coil composed of astrip formed from two plies of metallic foil uniform in width and arranged in staggered relation, an insulative coating on each ply and over the coalesced strip, the inner longitudinal edges of each ply being convexly curved to avoid sharp corners prior to being insulated, and terminal rivets fixed in the extending single plies at the ends of said coil, said coil being compressedover its main portion.

6. The process of making an electric condenser which consists of rounding one of the longitudinal edges of each of a air of uniformly wide strips of metallic foi passing the strips through a cleansing bath, and baths of liquid enamel of different density, drying the strips between each immersion, pressing the strips firmly together when in a tacky condition and in such manner that the rounded edges are innermost, Winding a Hattened coil from the coalesced strips, and inf serting a terminal conductor in the outermost edge portions of the coils at the end of the condenser.

7. The process of making an electric condenser Which consists of rounding one of the longitudinal edges of each of a pair of uniformly Wide strips of metallic foil, passing the strips through a cleansing bath, and baths of liquid enamel of different density, drying the strips between each immersion, pressing the strips firmly together when in a tacky condition and in such manner that the rounded edges are innermost, passing the coalesced strips through a third bath of dielectric material, cutting the stripto length, folding the ends of each component of the strip re-entrantly, and Winding a coil therefrom.

8. An electric condenser comprising a pair of foil strips of uniform Width arranged in staggered relation, said strips having their inner edges shaped to present rounded Surfaces.

This specification signed this 247th day of February, 1927.

' GEORGE EPAM BLIZIOTIS. 

